Dimension/measure group relationships

So far we've seen dimensions either having no relationship with a measure group or having a regular relationship, but that's not the whole story: there are many different types of relationships that a dimension can have with a measure group. Here's the complete list:

• No relationship

• Regular relationship

• Fact relationship

• Referenced relationship

• Many-to-many relationship

• Data mining relationship

We'll discuss many-to-many relationships in the next chapter because they are an important topic on their own, but before that let's talk briefly about the relationship types we've not seen so far.

Fact relationships

Fact or degenerate dimensions are, as we saw in Chapter 1, Designing the Data Warehouse for Analysis Services, dimensions that are built directly from columns in a fact table, and not from a separate dimension table. From an Analysis Services dimension point of view, they are no different from any other kind of dimension, except that there is a special fact...